For the past two years I've been using a WJ infrared model. It works very well for telling you the surface temperature in a split second. Problems I've had with it.....occasionally it switches to Celsius and for some reason it's hard to get it to switch back. Also, it's possible that the surface temperature can be several degrees warmer than the bottom.

I've also used several conventional stream thermometers. They are accurate and do not depend on batteries to work. They will also tell you the bottom temperature. Problem is you have to hold it in the water for about a minute for an accurate reading. This can be a tough chore when the water is frigid, deep or swift. I've used heavy line to suspend it and this works ok in slower moving water. You also have to be careful with thermometers containing mercury as not to break them in the stream.

Used both the IR and the conventional type. I like the conventional ones better, I tie some 2 mm cord to mine spot make taking a temp easier, but I have had them come unscrewed while hiking and Lose pat of the housing, requiring replacement more than once...

I use a Fishpond and have found it to be very accurate..... I am thinking about using a longer cord.....say 48" so I can check the temperature at different depths...... would be interesting to see if there is a significant difference at various levels............thats my story and I'm stickin' to it !!

I use a Fishpond and have found it to be very accurate..... I am thinking about using a longer cord.....say 48" so I can check the temperature at different depths...... would be interesting to see if there is a significant difference at various levels............thats my story and I'm stickin' to it !!

If the water is flowing the difference would be so small I doubt you could measure it unless the thermometer has 0.1 degree increments, and that assumes that pulling it back up wouldn't change it before you had a chance to read it.... Just my theory